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In this paper, a supercritical water oxidation treatment of coking wastewater . Coking wastewater is a complex composition , it is difficult to degrade toxic and hazardous high concentration of industrial wastewater , traditional biochemical processing of low efficiency . This study to establish a set of supercritical water oxidation the experimental device SCWO and CSCWO of experiments , for the treatment of major pollutants of coking wastewater COD, ammonia , cyanide , thiocyanate , the main product is CO2 , H2O, N2 . According to experiments , this experimental device of coking wastewater good treatment effect , and no secondary pollution . This experiment the reaction temperature is 400-500 ° C , reaction pressure of 24-30MPa, the oxidizing agent is an excess of H202 . Increasing the reaction temperature to increase the reaction pressure , to extend the residence time , increasing the peroxygen multiples , can promote the effect of the oxidative decomposition . Peracetic multiples of pollutant removal rate was less affected , select the first three factors orthogonal experiment to determine the impact on the treatment effect from small to large order : time , pressure , temperature . Single factor experiment in supercritical water oxidation reaction , cyanide and thiocyanate require a relatively low temperature and pressure , easy to reach better treatment effect , COD, ammonia requires a higher temperature and pressure in order to achieve the desired treatment effect . Cu (NO3) 2 , Mn (NO3) 2 , Fe (NO3) 2 as a catalyst for homogeneous reactions , further research to reduce the experimental parameters of the treatment of COD and ammonia nitrogen . According to experiments , the catalyst is added so that the reaction rate , reduce the temperature and pressure of the oxidation reaction , under the same experimental environment , with respect to the non-catalytic oxidation reaction of catalytic oxidation reaction , removal effect is significantly improved . Homogeneous catalytic supercritical water oxidation reaction Cu2 more appropriate as a catalyst . The reactor is made of 316L, have some corrosion under supercritical conditions , some adverse effects on the stability of the experiment . Experimental kinetic study of supercritical water oxidation , the establishment of the reaction kinetics equation .
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